A human corpse is on the receiving end of much of the so-called humor in “God’s Pocket,” but it’s the movie that feels dead on arrival, a strained pileup of small-town stupidity that might more honestly have been titled “Sad Sacks ‘R’ Us.”

Showing none of the sparkle of the five “Mad Men” episodes he’s directed, actor John Slattery makes a wobbly transition into feature filmmaking with this drab and uninvolving dark comedy about two parents reacting to their son’s suspicious death in increasingly hapless and hazardous ways. Philip Seymour Hoffman, Richard Jenkins and Christina Hendricks lead a strong cast left flailing by a gallery of underdeveloped characters, all of them stranded in a muddled indictment of provincial American life. This “Pocket” should be tucked away in short order.

It begins with the funeral of 22-year-old Leon (Caleb Landry Jones), accompanied by the voice of a narrator (Jenkins) who flatly describes the nature of life in the South Philly neighborhood of God’s Pocket, a boozy, blue-collar community where everyone knows everyone else’s business and nobody trusts an outsider. It’shomespun hokum-masquerading-as-wisdom though it does establish an air of pessimism that has its roots in Pete Dexter’s 1983 novel (adapted here by Slattery and Alex Metcalf).

The film takes us back to three days before the funeral, with Leon still alive and kicking, though not for long. A volatile, sociopathic troublemaker who works, if that’s the word, at a construction site, Leon makes the mistake of addressing an older black worker with a racist epithet that was probably more commonly in circulation in the ’70s, when the story is vaguely set. A retaliatory blow to the head leaves Leon dead; his boss and the various onlookers are quick to lie the cops, citing a simple workplace accident, though everyone else has suspicions to the contrary, wouldn’t you know.

While Leon’s nameless mother (Hendricks) retreats into an inconsolable cocoon, her husband, a hard-drinking lowlife named Mickey Scarpato (Hoffman), barely musters so much as show of grief, though he does go about making the funeral arrangements in the booziest, most idiotic way possible. At the time of his stepson’s death, Mickey was busy stealing a refrigerated truck with his buddies (John Turturro, Domenick Lombardozzi) to use in their illegal meat-hocking business, setting up the inevitable gag in which Leon’s corpse — jettisoned by the town’s unaccountably belligerant funeral-home director (Eddie Marsan) when Mickey admits he can’t afford the burial — will have to be placed in cold storage along with several sides of beef.

A third central character emerges in the form of Richard Shelburn (Jenkins, source of the opening narration), a newspaper columnist famed for his beautifully observed stories about the people of God’s Pocket. For all his local celebrity, however, he’s long since gone to seed, hooking up with random jailbait and drinking constantly. (He’s also, like Mickey, one of those untrustworthy outsiders mentioned at the outset.) His latest assignment involves looking into rumors that Leon’s death was no accident, though Shelburn is more interested in taking Mickey’s wife out on a romantic picnic. Their moment of sexual ecstasy, juxtaposed with the climax of Mickey’s cadaverous hijinks, represents the film’s nadir.

Flirting with outright nastiness but too toothless to follow through, “God’s Pocket” stirs to life at exactly two moments, both of them involving bloody spasms of violence that temporarily goose the picture out of its humdrum groove. With the possible exception of an Irish barkeep (well played by Peter Gerety), every character here is so sketchily written that even reliably great actors like Hoffman and Jenkins come off as nonentities; Slattery’s “Mad Men” co-star Hendricks emotes valiantly but similarly has nothing to work with.

In their choice of scrappy locations and understated ’70s furnishings (courtesy of production designer Roshelle Berliner), director and crew do a solid job of evoking an atmosphere of waste and ugliness, though the latter quality extends rather too literally to the film’s deliberately murky imagery — an uncharacteristic lapse for Lance Acord, the brilliant cinematographer behind films like “Where the Wild Things Are” and “Lost in Translation” (he’s also credited as a producer here).

Vic Damone, a pop crooner whose creamy baritone and heartthrob good looks propelled his success at the jukebox and on-screen in the post-World War II era, and for five decades more in nightclubs and concert halls, died Feb. 11 at a hospital in Miami Beach. He was 89.